Aerosol generating and propelling composition and insecticide



Patented May 5, 1953 AEROSOL GENERATING AND PROPELLING COMPOSITION AND INSECTICIDE Kenneth (3. Peer, San Francisco, and Llewellyn W. Fancher, Lafayette, Calif.

No Drawing. Application October 18, 1949, Serial No. 122,144

11 (Jlaims. 1

Our invention relates to the art of dispersing certain organic compounds into the atmosphere in a finely-divided form known in the art as an aerosol. Our invention produces such an aerosol of an organic compound by admixing it with a mixture of dry chemical agents which will react on initiation by local heat to produce large volumes of steam and other gases and which will produce sufiicient heat of reaction to propagate the reaction through the whole or the mixture, thus liquifying and then propelling the contained organic compound into the atmosphere with the rush of steam and gases.

An object of this invention is to provide a means of producing an aerosol of organic materials which cannot be directly volatilized by heat alone, due to their tendencies to decompose on reaching their boiling points, but which can be volatilized by codistillation with steam as in a steam distillation, which is a procedure well-known in the art of chemistry as a means for distilling many organic compounds at temperatures below their boiling points without substantial decomposition. More stable organic compounds may be equally well dispersed by means of our invention, but a distinct advantage of the invention is its ability to disperse the less stable compounds, many of which are widely used as insecticides, germicides, fungi cides and deodorants. Examples of insecticides which can be dispersed by our invention but which cannot be dispersed by heating to the boiling point without decomposition are: 2,2- bis(parachlorophenyl) 1,1,l-trichloroethane, 1,2,3, 5,6,7,8,8 octachloro 4,7 methano-3a,- 4,7,7a tetrahydroindane, beta butoxy beta thiocyano-diethyl ether, and beta thiocyanoethyl esters of aliphatic acids containing to 18 carbon atoms. An example of a germici-de is 1,3-hydroxy-4-hexyl benzene, and an example of a fungicide is pentachloro-phenol, both of which are unstable on boiling at atmospheric pressure and both of which can be dispersed by steam distillation and by the use of our invention.

Another object of our invention is to provide an aerosol of an insecticide, fungicide, germicide, or deodorant compound which will remain suspended in the atmosphere for a considerable time and which will deposit a thin film of the dispersed compound on exposed surfaces on extended contact, without the employment of auxiliary solvents or mechanical devices such as spraying machines, pumps, or steam generators.

Another object of the invention is to provide an aerosol of an organic insecticide which is substantially free of auxiliary solvents and which will provide a film of the insecticide on exposed surfaces that will not lose activity towards insects by virtue of absorbing into wood, fabric, or other absorbent materials, as is the case when substantial quantities of auxiliary solvents are present.

Another object of the invention is to provide a simple means of roducing an aei-osol of an organic compound as described above which can be safely handled, stored, and used by persons having no special skill or training without danger of spontaneous combustion or deterioration under extreme climatic temp r shock or confinement; which will not produce, in operation, sufiicient temperatures to cause ignition of paper, wood or fabrics; and which will not detonate by shock, spark or fire, in contrast to previously used combustible mixtures or mixtures employing ammonium nitrate or chlorates.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following description of the preferred form of the invention. It is to be understood, however, that variations in the process as described hereunder may be adopted within the scope of the invention as set forth in the claims.

Our invention employs our independent discovery that when potassium nitrate is mixed in approximately equal parts with sulfamic acid (amine sulfonic acid) as a dry powder and the resulting mixture is touched with a hot wire or flame in one localized portion of the powder, a reaction ensues which-produces large volumes of steam and gases and propagates itself throughout the whole of the mixture without reaching a temperature sufficient to cause glowing or visible flame o-r spark. This unexpected and unusual reaction does not occur when potassium nitrate is mixed in the same manner and touched with a hot wire or flame, with other inorganic acids, the ammonium salts of other inorganic acids, or organic acids, in our general experience. This reaction is quite different from the usual reaction of potassium nitrate in a combustion mixture, where a reducing agent such as charcoal, sulfur or oxidizable organic compound is present, in which cases large quantities of heat are produced with accompanying glowing, flaming and sparking. We discovered that this reaction was unique, in general, for the combination of nitrate salts and acid derivative of ammonia in the above-rea'ction has been found to cause the reaction to proceed more smoothly and to enable the reaction mixture to disperse higher proportions of incorporated organic material as described below.=

According to our invention, an organic compound which is to be dispersed into the atmosphere, as an aerosol, is added to a powdered or granular mixture of 2 parts nitrate salt, 1 part sulfur oxy-acid derivative of ammonia or an ammonium salt thereof, and 1 part of thiourea; the said organic agent being added in a quantity representing about 30 percent by weight of the final mixture. The proportions are variable within limits, but those indicated hereare the most generally satisfactory. The mixture thus produced can be initiated in reaction by a hot metal wire, a flame, or piece of igniting composition such as a fuse, whereupon the ensuing reaction propels the contained organic compound into the atmosphere in a finely divided form. The proportion of organic compound to the dispersing agents in the mixture is variable and is somewhat dependent on the physical properties of the compound. In general, the path of the reaction of the mixture on initiation, with or without the modifying agent of thiourea, is straightforward to the production of -steam, gases and heat, and little or no side-reaction occurs with the contained organic compound unless that compound be itself a nitrate or nitro-compound or a sulfonate.

In the preferred form of our invention we employ 2 parts of potassium nitrate, 1 part sulfamic acid (amine sulfonic acid), 1 part thiourea and 1 to 2 parts of organic compound to be dispersed. The ingredients are intimatelymixed in powdered or finely-granulated form. The final mixture is placed in a cardboard container, pressed into convenient forms such as, cylindrical or rectangular pellets, enclosed in non-combustible bags, or otherwise packaged suitably by means that would occur to those skilled in the art. Initiation of the reaction is started by means of a lighted match, a hot strip of metal or metal wire, an ignition fuse, or other convenient means which would be well known to those versed in the art.v

Other modifications of the invention can be made by those skilled in the art, such as the addition of odorant agents, the additionof inert 'mineralfillerssuch as fullers earth, china clay, expanded perlite and-the like for slowing the reaction rate and aiding the mixture in the accommodation of organic compounds which are tion, but are not intended to limit the invention thereto:

Example 1 Ingredient: Percentage by weight Potassium nitrate Sulfamic acid '20 Thiourea 20 2,2-bis(parachlorophenyl) 1,1,1-trichloroethane 20 The ingredients, in the proportions shown, are intimately mixed together in powder form and 100 grams placed in' a container. The reaction of this quantity was initiated by means of a lighted match in a 10,000 cubic foot chamber, and the contained insecticide dispersed into the chain'- ber atmosphere where it persisted for about} hours as an aerosol. Houseflies in cages in the chamber were killed within 24 hours and an insecticidal residual was deposited on exposedsurfaces which was active against housefiies for 8 days at a mean temperature of 70 F.

Example 2 Ingredient: Percentage by weight Potassium nitrate 35 Sulfamic acid .35 2,2,bis(parachlorophenyl).-1,1,1 trichloroethane '20 Mineral filler (expanded perlite, averag 30 mesh) 1Q Prepared and initiated as inExample 1;

Example 3 Percent Potassium nitrate 40 Sulfamic acid 20 l,2,3,5,6,7,8,8 octachloro 4,7 methano- 3a,4,7,la-tetrahydroindane (Chlordane) j, v3

Beta butoxy-beta'thiocyano diethyl ether and beta thiocyano ethyl esters of aliphatic acids containingplO to 18 carbon atoms (Lethane 384) 7 2,2-bis(parachlorophenyl) 1,1,1 trichloroethane 10 Thiourea 20 The dry solids are first intimately mixed an the proportions shown and the liquids (Lethane and Chlordane) added slowly and mixed thoroughly. Initiated as in Example 1.

Prepared and initiated as in Example l, lustrating the use of a fungicide and algacide.

Ingredient: Percentage .by weight Potassium nitrate 35 Ammonium imino sulfonate (di-ammonium amine disulfonate) 30 Thiourea 15 2,2-bis(parachlorophenyl)-l,1,l trichloroethane 20 Prepared and initiated 'as in- Example 1, 11- lustrating the use of an ammonium saltof 'a di-sulfonic acid.

Example 6 Ingredient: Percentage by weight Potassium nitrate 40 Sulfamic acid 20 Thiourea 20 Methyl salicylate l Expanded perlite filler 5 oxy-acid radicles to form the amine sulfonate or amine sulfinite salts of ammonia; e. g. ammonium amine sulfonate (ammonium sulfamate).

These sulfur oxy-acid derivatives of ammonia and their ammonium salts constitute the class of compounds we claim as a component in our invention as set forth below. The nomenclature is set forth in detail in the following recognized reference texts on inorganic chemistry:

Modern Inorganic Chemistry, J. W. Mellor, Longmans, Green & Co., New York, London and Toronto (1930) pp. 667 and 668.

Systematic Inorganic Chemistry, Don M. Yost and Horace Russell, Jr., Prentice-Hall, 1130., New York (1944) pp. 98, 99 and 106.

The proportions and sug ested ranges of ingredients may be further illustrated in the following examples:

1 2.2bis-(pu'a01il01o henyl)-l,1,1-trichloroethane. 2 l,2,3,5,6,7,s,8octac 1loro-4,7-methano-Ba,4,7,7a-tetrahydroindane.

residual film of insecticides on surfaces were also tested and demonstrated to be effective. Chemical determinations made on the collected aerosols in the examples above proved very efficient dispersion of the organic compounds from the powders into the atmosphere.

Some points of nomenclature concerning the sulfur-oxyacid derivatives of ammonia, which class of compounds is a basic component of our invention, may not be entirely clear, due to dual nomenclature in the literature of the art. To clarify exactly the identity of the class of compounds we claim as a component in our invention, we review below examples of the structural formulae of a series of sulfur oxy-acid derivatives of ammonia with their names as they appear in the literature of the art. As the examples, we show here the sulfonic acid derivatives of ammonia, in which one or more of the hydrogen atoms of the ammonia molecule is replaced by a sulfonic acid radicle (HSOa) which is an oxy-acid radicle containing sulfur:

H E303 E803 HSO; NCH NZH N-HSO: NHSOs H \H H803 Compound 1 is ammonia.

Compound 2 is amine sulfonic acid, amido sulfonic acid, or sulfamic acid.

Compound 3 is amine disulfonic acid, or imido sulfonic acid.

Compound 4 is amine trisulfonic acid, or nitrilsulfonic acid.

The other oxy-acid radicles containing sulfur, the most important one of which is the sulfinic radicle (HSOz) are substituted in place of one or more of the hydrogen atoms on ammonia in the same manner as shown above, the resulting compounds being the amine sulfinites, the amine sulfinic acids, the amide sulfinic acids and the imido sulfinic acids.

All of this class of compounds readily forms ammonium salts by the addition of the ammonium ion (NH4+) to one or more of the sulfur We claim:

1. An aerosol-producing composition for combatting insect pests which comprises an admixture of potassium nitrate approximately two parts, sulfamic acid approximately one part, thiourea approximatel one part and an organic insecticide which can be steam-distilled without substantial decomposition approximately one part.

2. An aerosol-producing composition for combatting insect pests which comprises an admixture of potassium nitrate 2 parts, sulfamic acid 1 to 1.5 parts, thiourea 0.5 to 1 part, and 2,2-bis(parachiorophenyl) -1,1,1-trichloroethane 1 to 2 parts, all parts by weight.

3. An aerosol-producing composition for combatting insect pests which comprises an admixture of potassium nitrate 8 parts, sulfamic acid 4 to 8 parts, thiourea 2 to 4 parts, 2,2-bis(parachlorophenyl) -l,1,l-trichloroethane 4 parts, and 1,2,3,5,6,'7,8,8- octachloro -4,'7- methano -3a,4,'7,'7atetrahydroindane 1 part, all parts by weight.

4. An aerosol generating and propelling composition for use in dispersion of materials capable of being transported and dispersed in an aerosol, comprising, the following reagents in approximately the following proportions, a nitrate salt two parts, a compound of the class consisting of sulfur oxy-acid derivatives of ammonia and the ammonium salts thereof one part, and thiourea one part.

5. An aerosol generating and propelling composition for use in dispersion of materials capable of being transported and dispersed in an aerosol, comprising, the following reagents in approximately the following proportions, potassium nitrate one part and a compound of the class consisting of sulfur oxy-acid derivatives of ammonia and the ammonium salts thereof one part.

6. An aerosol generating and propelling composition for use in dispersion of materials capable of being transported and dispersed in an aerosol, comprising, the following reagents in approximately the following proportions, a nitrate salt one part and sulfamic acid one part.

7. An aerosol generating and propelling composition. for. use in dispersion of materials capable of being transported and dispersed in an aerosol, comprising, the following reagents in approximately the following proportions, potassium nitrate one part and sulfamic acid one part.

9. An aerosol generating and propelling composition for'use in dispersion of materials capable of being transported and dispersed in an aerosol, comprising, mixture of potassium nitrate approximately two parts, sulfamic acid approximately one part and thiourea approximately one part.

10. An aerosol generating and propelling composition for use in dispersion of materials ca- "pable'of being transported and dispersed in an aerosol; comprising, the following reagents in approximately the following proportions:

-- Parts Potassium nitrate 2 Sulfamic acid 1 Thiourea up to 1 11. An aerosol generating and propelling composition for use in dispersion of materials capable' of being transported and dispersed in an aerosol, comprising, the following reagents in approximately thefollowing proportions: Y

, v, p v, j Parts Potassium nitrate 4 2 Sulfamic acid 1 to 1.5 Thiourea 0.5 to 1 KENNETH C. PEER. v LLEWELLYN W. FANCHER.

References Citedin thefile of this patent UNITED STATES PATENTS Number Name Date 2,224,622 Waples Dec. 10, 1940 "2,274,252 Tanberg Feb; 24, 1942 2,440,082 Flanders et al Apr. 20, 1948 2,455,205 Whetstone Nov. 30, 1948 FOREIGN PATENTS Number Country Date 22,002 Great Britain Sept. 16, 1893 of 1892 

11. AN AEROSOL GENERATING AND PROPELLING COMPOSITION OF USE IN DISPERSION OF MATERIALS CAPABLE OF BEING TRANSPORTED AND DISPERSED IN AN AEROSOL, COMPRISING, THE FOLLOWING REAGENTS IN APPROXIMATELY THE FOLLOWING THE PROPORTIONS: 